CN102265179A - Positioning signal sampling method and apparatus - Google Patents

Abstract

A method of processing data signals suitable for providing positioning information comprises sequentially recording blocks of data samples of a satellite broadcast from the beginning of a period of time of interest, and storing them in memory. When the memory is full, previously stored blocks of data samples are overwritten, such that the average quantity of sample data decreases, and wherein the memory content includes blocks of data samples covering substantially the full period of time of interest. This method enables blocks of data samples to be kept in memory for a full period of interest (for example a journey) but allows a limited memory capacity. The use of the memory is intelligent and dynamic.

Description

The method and apparatus of positioning signal sampling

Technical field

The present invention relates to be used in the storage of the employed data sample in position of determining events of interest or relate to the storage of the data sample in the path that is used for determining that device is followed, for example the data sample of global position system (such as GPS (GPS)).

Background technology

GPS is based on the navigational system of satellite, and this system is made up of the network of nearly 32 orbiters (being called as space carrier (space vehicle), " SV ") in 6 different orbit planes.This system design needs 24 satellites, and satellite but more can provide improved coverage (coverage).These satellites constantly move, make two complete tracks just in 24 hours around the earth.

By the gps signal of satellites transmits is to be commonly referred to as the direct sequence exhibition form of (DSSS) frequently, the pseudo-random code (pseudo-random code) that this direct sequence exhibition uses the mode with routine continuously to repeat frequently.Satellite broadcasting has several signals of different spreading codes, and this spreading codes comprises and provides free to rough/acquisition (Coarse/Acquisition) sign indicating number (C/A sign indicating number) of the public and give over to military confined accurate sign indicating number (Precise code) (the P sign indicating number) used of going up usually in advance.The C/A sign indicating number is 1023 long pseudo-random codes, its code check (chipping code) broadcasting with 1.023MHZ, and every millisecond is repeated once.Each satellite transmission allows by the different C/A sign indicating number of unique identification.

The data message is modulated on the C/A sign indicating number by each satellite; and comprise important information, such as the detailed orbit parameter of launching an artificial satellite (being called as ephemeris (ephemeris)), state (normal or undesired), current date, and time about the information of the clocking error of satellite, satellite.This part of signal determines that to gps receiver the position is absolutely necessary accurately.Each satellite is only at itself emission ephemeris and detailed clock corrected parameter, and therefore independently (unaided) gps receiver must be handled it wants the data message of each satellite of using in location Calculation suitable part.

The data message also comprises so-called astronomical year book (almanac), and it comprises about the more inaccurate information of all other satellites and less being updated.Almanac data allow gps receiver the random time of whole day estimate each gps satellite should the position, it is more efficient to make this receiver can select which satellite to search.The astronomical year book data of the orbit information of each satellite in each satellites transmits display system.

Traditional gps receiver reads the data message of emission and preserves ephemeris, astronomical year book and other data commonly used.This information also can be used to set the clock in (or correction) gps receiver.

In order to determine the position, gps receiver is compared with this signal the time of satellite emission signal by the time that gps receiver receives.How far this mistiming tells this particular satellite distance of gps receiver.By in conjunction with range observation, can pass through trilateration (trilateration) and obtain the position from a plurality of satellites.Utilize minimum three satellites, gps receiver can be determined lat/lon position (2D location).Utilize four or more a plurality of satellite, gps receiver can determine to comprise latitude, longitude, and the 3D position of height.The information that receives from satellite also can be used to set the interior clock of (or correction) gps receiver.

By handling the tangible Doppler displacement (Doppler shift) from the signal of satellite, gps receiver also can provide the speed and the direction (being referred to as " ground speed " and " ground trace ") of advancing exactly.

Nearly all current GPS receiver all by when the signal from satellite enters " in real time " handle this signal and the report this device work in the position of current time.This " traditional " gps receiver always comprises:

-be suitable for receiving the antenna of gps signal,

-analog radio frequency (RF) circuit (being commonly called the GPS front end), it is designed to come that signal to expectation amplifies, filtering, and be mixed into intermediate frequency (IF) downwards, thereby make they can be with the sampling rate (sample rate) of normal several approximately MHz by suitable simulation to numeral (A/D) converter

-digital signal processing hardware, it carries out relevant treatment to IF data sample that A/D converter produces, and combines with the microcontroller of execution to a certain form of the processing of the location of controlling this signal Processing hardware and calculation expectation very necessary " higher level " usually.

The notion of very infamous " catching and handle after a while (Capture and Process Later) " also is studied.This relates in after a while time (several seconds, a few minutes, several hours or even several days) and is handling more a certain other the position of resource usually and handling before the collected IF data sample of traditional antenna and analog RF circuit, and they are stored in the internal memory of a certain form.

The method of catching and handling after a while is with respect to the major advantage of traditional gps receiver, owing to when catching, need not to carry out digital signal processing, therefore the cost and the power consumption of acquisition equipment are retained as minimum value, and capture time can be lacked (for example, 100ms) very much.If under the situation that can obtain relevant satellite data (ephemeris etc.), finish follow-up signal Processing by certain additive method, this method also need not to decipher (very slow) data message from SV in acquisition equipment, and the time that this decoding can cause needs can not accept length under many circumstances starts (start up) traditional device.

A problem of gps system is, the GPS environment may be difficult sometimes, for example indoor or in " urban canyon (the urban canyon) " between high-rise, so that possibly can't use GPS to position.The sensitivity of GPS can be modified, and it can help head it off, but can not solve fully, because the situation of satellite-signal deficiency is always arranged.Because performed extra calculating and processing, the increase of sensitivity has also increased power consumption and cost.

Follow the trail of solution the direction of advancing is provided, can follow the tracked difficult environment that enters and pass as the position of finding out of doors.By this mode, sensitivity can be improved substantially, and good performance is provided often." last known position (last known position) " also can be reported.But tracing system can consume power consumption continuously, though in fact the result is not used-and this track also must be kept in case required after a while.

Other method is to utilize the low-power usage of the method for catching and handling after a while, and stored samples is used for handling after a while.But the storage of sample will be used and finally can fill the available internal memory capacity.The internal memory that abundance possibly can't or be provided satisfactorily is to store catching of all expectations at the given operating cycle.If duration the unknown of operation (for example, if positioning system is used for the stroke of unknown concrete duration) also may unpredictablely become full and carry out the frequency of catching for fear of free memory.

If it is full that internal memory becomes, can stop to collect data capture, but this will mean and not obtain nearest data.Selectively, internal memory can be operated in circulation (circular) mode (FIFO), so that nearest data are saved.These selections (option) all can not provide the optimum operation mode of the internal memory that uses limited capacity.

Summary of the invention

According to an aspect of of the present present invention, provide a kind of processing to be suitable for providing the method for the data-signal of locating information, this method comprises the following step:

Sequentially write down the blocks of data samples of satellite broadcasting from the beginning of interested time period, and they are stored in the internal memory;

In response to being full of sequential element in the internal memory, continue record data sample block sequentially, and rewrite the previous blocks of data samples that stores, make the par of sample data reduce, and wherein memory content comprises the sample block that covers the whole interested time period in fact.

This method makes sample can keep the whole interested time period (for example, whole stroke) in internal memory, but allows limited memory size.The use of this internal memory be intelligence and be dynamic.

This method need not to predict the length of interested time period.Therefore, need not the planned sampling rate attempts to arrange internal memory to be full of when this interested time period finishes just.

This method makes memory information that complete distance information can be provided under the situation of given memory source as far as possible exactly.

Preferably, the par of the sample data of each sequential element reduces, and the par of each sample data of defined sequential element during initial internal memory is filled reduces more specifically.This means and the initiation sequence element between data volume in corresponding time period of time of (being between internal memory the catching when initially being filled).

In an example, can be periodic in order to the sequence of filling internal memory, promptly section of per set time is carried out one and is caught.In this case, each sequential element is associated with identical duration section, and the par of the sample data of each sequential element is equivalent to the amount of the memory source that time per unit distributes.Therefore, this mean value is relevant with the time.

In another configuration, described sequence can comprise the time variable between the sequential element.For example, between catching constant distance can be arranged, for example, the wheel of every given number changes (wheel revolution) and once catches.In this case, each sequential element was associated with different time period between catching.The par of the sample data of each sequential element then is equivalent to the amount of the memory source that per unit distance (that is, the wheel of every given number changes) distributed.Therefore, this mean value and distance dependent are although it should be noted that the degree relevant with the time reduces.

Therefore, when internal memory is filled, sequence between catching, can have regular time section or its can have the variable time period, and this variable time period can owing to other reason produce rather than since the per unit distance catch generation.

As time goes on the par of sample data can two kinds of main modes reduce.

First method is that arrange to rewrite section averaging time that makes between the blocks of data samples of adjacent sequential (time-sequential) storage elongated.For example, may catch (1 of time per unit is caught) in that moment t, t+1 and t+2 are existing.By rewriteeing catching of t+1 constantly, catching t and catching t+2 is catching of adjacent sequential now, and increases to 2 from 1 at interval.Identical method can be used for not the sequential element of constant time at interval.

With regard to periodic sequence, this catches data with one of time per unit and reduces to 0.5 of time per unit and catch corresponding.Therefore, there is a group of covering the whole interested time period to catch, but has step by step catching that wide interval more is retained.

Second method is arrange to rewrite to make the par at the sample data of given sequential recording (that is, catching) reduce.For example, can store the blocks of data samples of 200ms at time t, t+1, t+2.Can use the data of different 100ms constantly to rewrite half of catching the occupied internal memory of t+1, so that all catch the duration that progressively becomes 100ms.This will make the capacity of the sample data of each sequential element reduce by half.

In either case, can obtain complete historical track (trail) (comparing) with the use of simpler cyclic memory.

Periodically the time period of record data sample block can be elongated in time, especially for above-mentioned first method.

Overwriting data is caught by this way, that is, and compare in the relative time early, and the data capture in the internal memory is received in (populate) more thick and fast in the nearer relatively time.

This method is interested for the application that device can be carried out location Calculation.In this case, the irregular pattern of catching of definition in internal memory wherein has more near the time of request location and catches.Therefore, more and nearest history-sensitive information was arranged in the internal memory before desired location.

In this case, in response to the request that the position of the special time during the interested time period is determined, can handle to attempt obtaining the location nearest blocks of data samples.

If it is unsuccessful to attempt obtaining the location, the recorded data sample block was handled when this method can further comprise the time in the sequence early, obtained the location with further trial, till obtaining the location.

This provides the localization method outside a kind of normal satellite receptivity, and provides in sample block daily record (log) At All Other Times and catch and store.If the location of being asked is unsuccessful, then nearest sample block is used to set up last known position.

This method can further comprise the request of determining in response to the position and write down the blocks of data samples of additional satellite broadcasting, thereby forms nearest blocks of data samples.This means that exhaust may be near the sample block of expected time.

Obtain after the location, can use the additional information of successfully attempting to attempt again at unsuccessful trial.This makes and can obtain formerly can not obtainablely to locate.

Can before the location that is obtained, repeatedly obtain the location, thereby form location track.This can cover the whole interested time period.

Record and processing can be carried out on the portable, battery powered device.For example, between the time of shipment, the follow-up mechanism that this device can be to use container to provide so that can obtain position history, and can be replied the request to current location.

Data capture can be rewritten by this way, that is, in the interested complete time period, the data capture trend in the internal memory is received in (about time or distance) in fact fifty-fifty, rather than nearest catching more thick and fast is received in.This may be applicable to record (logging) device, and this pen recorder provides track history but real-time positional information is not provided.In this case, be recorded on the portable, battery powered device (register) and carry out, and handle and on independent device, to carry out, after the interested time period, be downloaded on this independent device from the data of mancarried device.

In all cases, sample can comprise the data sample of intermediate frequency down conversion.

The present invention can be implemented as computer program.

The present invention also provides the equipment that is suitable for providing the data-signal of locating information in order to processing, and this equipment comprises:

Internal memory;

First receiving device, it is suitable for sequentially writing down from the beginning of interested time period the blocks of data samples of satellite broadcasting;

Processor, it is in order to the storage of the blocks of data samples in the control internal memory;

Wherein processor is adapted to:

Be full of sequential element in response to internal memory, continue record data sample block sequentially, and rewrite the previous blocks of data samples that stores, make the par of sample data reduce,

Wherein memory content comprises the blocks of data samples that covers the interested complete time period in fact.

This equipment can further comprise treating apparatus, and it handles nearest blocks of data samples to attempt obtaining the location in response to the request that the position of the special time during the interested time period is determined.

Description of drawings

By the mode of example the present invention is described below with reference to accompanying drawing, wherein:

Fig. 1 show be suitable for catching and handle operation after a while and can be used to implement gps receiver of the present invention;

Fig. 2 shows first example of method of the present invention; And

Fig. 3 shows second example of method of the present invention.

Embodiment

The invention provides the method that a kind of processing is suitable for providing the data-signal of locating information, wherein use the internal memory of limited capacity to come the storage data sample block.This internal memory is rewritten intelligently, make the quantity of average sample data reduce according to catching, but memory content comprises the sample that covers the complete interested time period in fact.This means that internal memory can recover data track at the complete duration.Finish to be spaced apart 10 minutes (being an example at random) if catch, then may not have in preceding 10 minutes of stroke and catch.But in fact all stroke still can be regarded as by the data representation in the internal memory.Therefore, preferably, catch at a time period for the first time, this time period is no more than the time of the interested time period that is equivalent to the maximum time between other is caught in the internal memory after beginning.In fact, instead, the complete time period can be regarded as the interested time period at least 90% or more preferably for the interested time period 95%.

The present invention uses in can using in the global function gps receiver or catch and handle after a while and using.But in each case, this device is implemented a kind of catching and the form of processing capacity after a while, is used in the internal memory in the future using obtaining the location because data capture is stored in.

In the application of typically catching and handling after a while, the weak point of IF data sample " is caught " the little acquisition equipment that is stored in the internal memory can in fact its IF data capture be uploaded to shared central computer, this central computer will not only be carried out important signal Processing (correction etc.), but also can be by being connected to the database that one or more traditional gps receivers visit nearest satellite information (ephemeris etc.), the key component of the gps data message that described one or more traditional gps receivers are received with them is pass on to this central computer.

Fig. 1 is the system diagram of the gps system catching and handle after a while.Signal from gps satellite is received by antenna 10, in the unit 12 that drives by reference oscillator (being generally temperature compensating crystal oscillator) 14, carry out traditional simulation process then, this simulation process typically comprises the combination of amplification, filtering and downward mixing, carries out the A/D conversion subsequently in unit 16.This is the radio reception electron device of traditional formation RF front end.

The controller 18 that is implemented as discrete logic components or has a microprocessor of relevant firmware is selected will be stored in part in the storage device 20 (for example, flash memory ram, hard disk etc.) by the sampling IF data that the RF front end is produced.Mode wherein is subjected to the user to set the influence of the use of (as by GUI (graphic user interface) 22 input) and timer 24, timer 24 also can by shown in oscillator 14 drive.

The off-capacity that the invention particularly relates to internal memory 20 is caught so that the application that needs internal memory to rewrite with the complete expected time section of the use of writing down this device.

Timer 24 may simply be the counter by oscillator drives, and perhaps it can be real-time clock (RTC), and this real-time clock keeps date and time even when this device is switched off.Can have independent oscillator that the energy of " turning off " is used minimizes.

When being activated, this device recording is from the IF data short block (these short blocks are called as " catching " hereinafter) of RF front end and the timestamp from timer 24 (timestamp) that is associated.These are caught can be that for example 100ms is long, and they can with clocklike at interval (regular interval) be recorded, for example every 10s is once.Typically, the RF front end provides sample flow with the speed of 6MHz, and catches the data (that is 0.6 or 1.2 million sample) of the 100ms that comprises this sample flow (or for example 200ms).Employed exact value can be changed by GUI 22 clearly or impliedly by the user.In different application, catching of different length will be suitable.Typically, each catch with subframe (subframe) duration than 6s shorter, and preferably be less than 500ms.

Preferably, the energy consumption in the time period between catching is minimized by the assembly as much as possible of turning off gps receiver.The minimal set of assembly (comprising timer 2 4) keeps activating, " to wake " receiver up in next capture time.Therefore, this device may be implemented as battery powered mancarried device, and therefore battery life can be extended.

In pure catching and handle in the application, it all is to obtain to upload the recorded data sample by this device being connected to computing machine that any position is determined.Be provided with in the application of full GPS function at this device, this system also comprises required processing power, to obtain the location from record or real-time sample.

The present invention relates to a system, wherein the daily record (" catching " means the record block of GPS IF sample) of catching of the information that the position is relevant is received and is stored to be used to provide location estimation after a while.Therefore, additional catching is used to those location estimation of being obtained when the expectation location.

Additional catches the whole duration that spreads all over " interested time period ", this means the time period of expectation location continuously.With regard to data recorder or tracker, the interested time period will be an one stroke.As time goes on the density of data reduce.

In an example, catching can be clocklike to be received and to be stored at interval, although this is not requisite, described in hereinafter.Application will be depended in this interval, especially depend on the desired speed that device moves and the degree of accuracy of desired position.For example, at the tracking of long haul, per 5 minutes periodically the sampling once will enough understand the position that conveys goods.At the tracking of motorcycle along the path that a route is advanced, it may be more suitable that one of per second is caught.Catch with being stored in their indication of received time.

Internal memory 20 has a capacity, and this off-capacity is caught with all possible duration of using with the best ratio pen recorder, and the invention provides various internal memories and rewrite schemes.

Fig. 2 is in order to explain method of the present invention.

The beginning of step 30 expression interested time period (for example one stroke).In step 32, receiver is from the blocks of data samples of the opening entry satellite broadcasting of interested time period, and they are stored in the internal memory as acquisition sequence.If record is clocklike to carry out at interval, then catch at interval uniform time quantum (that is, each catches the regular time amount that relates to), but record can carry out otherwise, for example move (that is, each sequential element relates to fixing distance measurements) with fixed range unit.

Expire when internal memory becomes, re-writing step 34 continues record data sample block sequentially, but rewrites the blocks of data samples that before had been stored.

This rewriting is not to carry out with the form of cyclic buffer, covers catching of interested complete time period but keep.But the par of the sample data of each sequential element of interested time period reduces.The end of interested time period is shown in step 36.

Rewriting can be configured so that section averaging time between the blocks of data samples that the contiguous time stores increases, and perhaps makes the par of given data sample of catching reduce." contiguous time blocks of data samples " is meant the blocks of data samples of getting at these two time points (, catch) when other that do not have two times between the time point in the internal memory are caught.Interval between the sequential element of record data sample block can increase along with the time, because along with the prolongation of time period, was captured on the time (or distance) and became farther step by step.

In a kind of configuration, catch in time and to keep distributing in fact equably (that is, internal memory comprise catch one of every t second).Certainly, rewriting will cause certain scrambling, but the rewriting scheme can be designed to tend to this homogeneity.But, alternative scheme is that the irregular pattern of catching can be held (retain), for example, has frequent catching recently, but older the catching of great majority is dropped with the releasing memory capacity, keeps catching to provide of several Geju City to have the rough image that moves than the history of hanging down reliability simultaneously.

But, in each case, catch the time period that all spreads all over the device activation, catching of storage is progressively thinning thin.Thereby, for example, be used for during several days time period and the record of periodic is followed the trail of:

Can store 1 in per 5 minutes in first day and catch,

Then, rewrote catching of even number in second day so that when finishing in second day internal memory comprise per 10 minutes 1 catch,

Then, the 3rd day and the 4th day rewrite first day and second day stored catch half so that when finishing in the 4th day internal memory comprise per 20 minutes 1 catch, by that analogy.

Therefore, in any specific time, the interval between maintained the catching of being stored so far changes at whole track.After a while, when track is longer, interval and variation will be different.

Catching in the internal memory is used for the GPS location.This can be in real-time clock, according to the request (together with the information such as the satellite ephemeris supplementary) to position calculation.Selectively, catching and after a while in the treating apparatus, can after this device is uploaded, positioning, be used on the personal computer (PC) that connects, positioning in data.

Two examples of the possible use of this system are discussed hereinafter:

(i) honeycomb fashion follow-up mechanism

This device receives gps signal and stored in per 5 minutes catches (they not being handled).In case internal memory is full of, catches with intelligent manner and sequentially rewritten.This device has the cellular phone performance, but so that the Location Request of its receiving remote.Cellular network provides required current and historical satellite information for this follow-up mechanism, and the request location.

Then, this device can be got (alternatively) new GPS and catch, so that there are the data of the positioning time of approaching as far as possible expectation.Then, attempt using location current and recently to come calculating location.Then, also can calculate previous history location, to obtain the motion track of this device.Give cellular network with this trace reporting.

In this example, priorly may provide accurate other position rather than evenly accurate historical track.Therefore, can select internal memory to rewrite and support nearest the catching in addition of (favour) possible position requests.

Therefore, remain on desired pattern till catching in the internal memory can be followed current point in time.By way of example, can begin to retreat from current point in time and keep one group at set intervals and catch, for example:

In last two hours per 5 minutes;

Each of the previous day hour;

Last week per 6 hours or the like.

If the GPS Location Request is not received, then rewrite in default mode (as mentioned above) and carry out, As time goes on packing density progressively diminishes.

As can be seen, in this example, maintainedly be captured in nearer relatively time internal ratio and in the time relatively early, be received in more thick and fast.Have fewly, and have identical more low-density periodic acquisition-and catch excess time along with internal memory is progressively further rewritten and reduces to two kinds of different rules-so that there is a high density phase of catching.

(ii) register

This device receives and storage location is caught, for example, and per 5 minutes or per 20 meters.It can not receive real-time position requests, and is used for historical tracking simply.In this case, packing density (time per unit or distance) can be kept equably at the whole interested time period.

When stroke finishes, to catch and be uploaded to the PC that is connected to communal facility, positioning track is caught and is produced in its processing.At in order to store the pen recorder of a plurality of tracks, internal memory utilizes system can only be used for current track again.

Below will describe, and only use 9 memory slots to describe an exemplary simple algorithm.This example is based on using the catching of regular length (for example, 100ms or 200ms) data rewrite rather than given sampling data bulk is constantly tailed off, and catching based on regular time intervals.

This method provides bout formula data to write.In first leg, write data to fill internal memory with the first default cycle of catching.For convenience of explanation, use catch the cycle (but can adopt any other value) of 1s.Therefore, when first leg finishes, finished catching of 9 1s intervals.

In all bouts subsequently, half of memory slot is rewritten, and refers to 4 grooves (when decimal during by round down, 4 is half of 9) in this case.But at each bout, the cycle of catching doubles (therefore, the cycle of catching of second leg is 2s, and the cycle of catching of the 3rd bout is 4s, and the cycle of catching of the 4th bout is 8s or the like) at every turn.The groove that is rewritten is that those comprise from the groove of catching of time of multiple that is not the cycle of catching of this bout.

Below show this process, wherein the data that in bout title Z, write second of data block Zn indication at time t=n:

First leg A:

1 second catch the cycle, all grooves are filled.

Groove: 012345678

A0 A1 A2 A3 A4 A5 A6 A7 A8

Second leg B:

2 seconds catch the cycle, half of groove is filled.

Groove: 012345678

A0 B10?A2 B12?A4 B14?A6 B16?A8

Catch B10, B12, B14, B16 are written into, and have rewritten A1, A3, A5 and A7 (because 1,3,5 and 7 be not 2 multiple).

The 3rd bout C:

4 seconds catch the cycle, half of groove is filled.

Groove: 012345678

A0 C20?C24?B12?A4 C28?C32?B16?A8

Catch C20, C24, C28, C32 are written into, and have rewritten B10, A2, B14 and A6 (because 10,2,14 and 6 be not 4 multiple).

The 4th bout D:

8 seconds catch the cycle, half of groove is filled.

Groove: 012345678

A0 D40?C24?D48?D56?D64?C32?B16?A8

Catch D40, D48, D56, D64 are written into, and have rewritten C20, B12, A4 and C28 (because 20,12,4 and 28 be not 8 multiple).

The 5th bout E:

16 seconds catch the cycle, half of groove is filled.

Groove: 012345678

A0 E80?E96?D48?E112?C32?E96?B16?E80

Catch E80, E96, E112, E128 are written into, and have rewritten D40, C24, D56 and A8 (because 40,24,56 and 8 be not 16 multiple).

This example simply illustrates, and can make the robotization of internal memory overwrite function in simple mode.

Preferably, catch by timestamp and explain (annotate), but various other attributes can be recorded with the IF data capture, comprising:

(i) date and time (in known time system);

The (ii) identifier or the value of RF front end characteristic (such as sampling rate, centre frequency, oscillator type/attribute etc.);

(iii) data layout (syllable sequence of data, order, the plural number/real number notation (notation) of position when each sample has more than 1);

The (iv) identifier of mounted cast (or or even unique device ID).

Above-mentioned example need not any from external device (ED) input and carry out Memory Allocation, and be suitable for register and use.Can strengthen Memory Allocation to allow the real time position request and to improve the location that obtains.

Fig. 3 is a process flow diagram, and it shows in device has completely the example of the present invention of GPS function (such as above-mentioned given tracking example), and how this method is in order to obtain the location.This packing density with the time per unit of above detailed description reduces and the irregular distribution of memory size combines, and making has more relatively data to use near the positioning time of expectation.

In step 40, IF GPS sample block is carried out periodic sample, for example, 200ms duration and 1s be (as example arbitrarily) at interval.Memory size be not enough to store the given operating cycle all catch, therefore in step 42, have above-mentioned data rewrite.

In step 44, the request at the position is arranged.Alternatively, this can cause the further GPS sampling shown in the step 46, so that a GPS catches the correct time that is in.Selectively, recently catch and replacedly to use.

In step 48, device is attempted the location based on nearest catching.System can provide A-GPS information (satellite " ephemeris ") positioning trial based on historical GPS sample.If trial and success for the first time, this method finishes (and turning back to periodic sample and rewriting).If attempt for the first time unsuccessful, uses previous data and according to the time the sequence of morning further attempt.Further attempt representing by module 50 at every turn, and according to alternative manner, till obtaining the location.In case arrive the time point (for example) that finds satellite, then can obtain the location because the user at that time out of doors.

Irregular the catching of using regularly means and do not carry out repeated attempt when can not be successful.For example, if before present, 5s or all can not obtain the location before the 10s, then before 15s, can not obtain the location.Instead, ensuing catch may be before 1m, before the 2m etc.

Then, have optional step 52, this step uses the additional information that can obtain from successful location (that is, the knowledge of apparent position and time, for example, it can make visible satellite be determined) to attempt previous kaput location again.This even the GPS that can produce at the current request of before having failed locate the location of catching.

After finishing dealing with, the process end also is back to periodic sample.

In above-mentioned application, except the position of request time, also expectation obtains moving historical.Therefore, to before the position requests more early catch the historical track of handling with display position.

Mentioned above principle can be used for any GPS device, comprises special-purpose GPS/GSM (global system for mobile communications) follow-up mechanism, GPS phone, video camera, television camera.

Obtaining the required processing in location based on the GPS sample is traditional processing.It comprises estimation and trilateration at the flight time of the search of the IF sample of the signal of SV as much as possible, these signals basically, to obtain the position.In this stage, the almanac data of download can be in order to guiding search.For example, As time goes on understand request time and the position of each SV, only some SV is as seen concerning receiver in given position.Therefore, in case find and a corresponding signal of SV, then can from search, get rid of visible a plurality of other SV simultaneously.

As mentioned above, writing down the sequence of catching at first can be on time or distance equably at interval.Therefore, " sequential element " is a part that is assigned to specific sequence of catching, and it can have constant time length (for example, first 10s is corresponding to first " sequential element ") or it can have constant distance (for example, first 10m is corresponding to first " sequential element ").The minimizing of data is used for two kinds of sights in an identical manner, for example:

Interval (for example, the interval of 20s or 20m being arranged between stored the catching) between-the increase sequential element, or

The data (for example, first 10s has the data of 100ms rather than the data of 200ms, and perhaps first 10m has the data of 100ms rather than the data of 200ms) of each sequential element of-minimizing.

The sequence of more generally, catching can be by any suitable trigger control.Above-mentioned two examples relate to the trigger of clock or range observation collocation form, but other outside trigger also is feasible, and for example the user enters the different bands of position at every turn and then provides one and catch (having write down moving rather than mobile in the zone between the zone so that catch).Also can control and catch, provide the prime opportunity that obtains the location so that catch based on signal strength measurement.Therefore, have many possible modes initially to fill internal memory, and when rewriteeing memory content, the present invention can be used for all these modes with sequential element.

There is other possibility, the GPS measurement of catching is combined with honeycomb fashion information (base station, frequency measurement, timing advance), locate with acquisition as the part of handling.

Additional input can be in order to the mode of Control Allocation internal memory.For example, the indication of battery level can be in order to the control sample period, so that save (conserve) power of battery when needing.

Described global function GPS (have ephemeris auxiliary) or caught and handled two examples of enforcements (have and upload the IF data that are used to handle), but can have other enforcements between extremely at these two.An example is so-called assisted global position location satellite system (Assisted-GPS) solution, and the server that has ephemeris and can carry out the location is handled and then they are uploaded to its processing with regard to pseudorange.

In above-mentioned all different forms, this method needs few power consumption, it is not handled usually because only catching the gps signal sample.The GPS receiver need be opened, but thereby gps signal-this is much smaller than in order to recover and to measure gps signal itself and the required energy of execution signal Processing compute location to receive.Importantly be only when the request location, just need consume the processing energy.

Described the present invention in conjunction with (single-frequency) GPS, but other Global Navigation Satellite System (GNSS) (GLONASS, Galileo etc.) will be similar with it.In fact, this technology also can be used for multi frequency system.

Below only provide a kind of overview of system configuration.But, it will be understood by those skilled in the art that the variation (with regard to the internal memory rewritable versions) that the present invention can simply be embodied as remains on the data in the internal memory, perhaps simply be embodied as the variation of the selection of data to be processed.The variation of each function can utilize the hardware of complete standard to implement, and utilizes the variation of the software that will carry out to implement.Therefore, have the system configuration that does not have detailed description, and many different versions all are feasible.

Various other modifications also will be conspicuous to those skilled in the art.

Claims (15)

1. a processing is suitable for providing the method for the data-signal of locating information, and this method may further comprise the steps:

Sequentially write down the blocks of data samples of satellite broadcasting from the beginning of interested time period, and they are stored in the internal memory;

Become full in response to internal memory, continue record data sample block sequentially, and rewrite the previous blocks of data samples that stores, make the average sample data bulk reduce, and wherein memory content comprises the sample block that covers the whole interested time period in fact.

2. the method for claim 1, it is elongated wherein to rewrite section averaging time that makes between the blocks of data samples that stores chronologically.

3. the method for claim 1 wherein rewrites the average sample data bulk that makes given sequence write down and reduces.

4. as the described method of above-mentioned each claim, wherein sequentially the interval between the sequential recording of record data sample block increased along with the time.

5. as the described method of above-mentioned each claim, wherein so that the average sample data bulk in the nearer relatively time greater than the mode overwriting data sample block of the average sample data bulk in the time relatively early.

6. method as claimed in claim 5, it further comprises following steps:

Request is determined in position in response to the special time during the interested time period, handles nearest blocks of data samples to attempt obtaining the location.

7. method as claimed in claim 6, if wherein the trial of acquisition location is unsuccessful, this method further comprises recorded data sample block when the time is than morning in the processing sequence, obtains the location with further trial, till acquisition is located.

8. method as claimed in claim 7, it further comprises in response to the position determines request, the blocks of data samples of the satellite broadcasting that record is additional, thus form nearest blocks of data samples.

9. as claim 7 or 8 described methods, wherein after obtaining the location, use the additional information of successfully attempting that unsuccessful the trial attempted again.

10. as each described method in the claim 7 to 9, it further comprised at a plurality of times before the location that is obtained, and obtained a plurality of location, thereby formed location track.

11., wherein write down and handle on the portable, battery powered device and carry out as each described method in the claim 6 to 10.

12. as each described method in the claim 1 to 4, wherein so that the trend of the blocks of data samples in the internal memory has the mode overwriting data sample block of the sample data of equal number in the whole interested time period.

13. method as claimed in claim 12 wherein is recorded on the portable, battery powered device and carries out, and handles and carry out on independent device, the data from mancarried device after the interested time period are downloaded on this independent device.

14. as the described method of above-mentioned each claim, wherein sample comprises the data sample of intermediate frequency down conversion.

15. a processing is suitable for providing the equipment of the data-signal of locating information, this equipment comprises:

Internal memory;

First receiving device, it is suitable for sequentially writing down from the beginning of interested time period the blocks of data samples of satellite broadcasting;

Processor, it is in order to the storage of control data in EMS memory sample block;

Wherein processor is adapted to:

In response to the internal memory that is full of sequential element, continue record data sample block sequentially, and rewrite the previous blocks of data samples that stores, make the par of sample data reduce,

Wherein memory content comprises the blocks of data samples that covers the whole interested time period in fact.

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